The Healthy Women Study is the only longitudinal study of the premenopause through the postmenopause periods that includes detailed measures of biochemical, hormonal, behavioral, and genetic variables in a defined group of women followed at specific intervals. The study has been very successful in maintaining 500 of 541 women in the study over 7 to 8 years. Approximately 54% of the women have become menopausal with about one-third of them taking hormone replacement therapy (HRT). Menstrual cycles prior to menopause have been carefully tracked. The menopausal period results in a substantial increase in LDLc of approximately 3 mg/year, a decline in HDL2c, an increase in fibrinogen, glucose, and possibly waist-to-hip ratio. Other variables increase primarily due to aging, weight gain, or changes in lifestyle such as alcohol consumption, cigarette smoking, diet, exercise, and social/behavioral variables. Family history of heart disease, diabetes and hypertension, and apoprotein polymorphism are related to both the baseline and possible changes in risk factors. Most women have few adverse psychosocial changes during this time. The results to data demonstrate that women develop an atherogenic profile during the peri- to the postmenopausal period, which probably increases their risk of atherosclerosis and subsequent clinical coronary artery disease. The investigators propose a five year study to evaluate these changes from the premenopausal to the late postmenopausal period up to or around age 60 to 62 in this population. They would evaluate the changes in risk factors, behavior, hormones, clotting factors, and also add measures of atherosclerosis using duplex scanning of the carotid and abdominal aorta and blood pressure and heart rate reactivity to mental stress. This would provide a unique picture of the determinants of cardiovascular health from premenopause to age 60+ in a carefully evaluated cohort of women. The investigators point out that the study combines expertise in epidemiology, behavioral sciences, endocrinology, gynecology, biostatistics, genetics, and nutrition. They state that it has become the cornerstone of a major research effort in women's health.